Lise Meitner (7 November 1878 – 27 October 1968) was a leading Austrian-Swedish physicist who played a key role in the discovery of the nuclear fission. She spent a substantial part of her career in Stockholm.
To commemorate her the colloquium-style distinguished Lise Meitner memorial Lecture and Medal takes place annually at the AlbaNova university centre.
The Lise Meitner Distinguished Lecture is sponsored by Royal Swedish Academy of Sciences through its Nobel Committee for Physics.
Speaker: Peter Shor (Massachusetts Institute of Technology)
The Magic of Moiré Quantum Matter
Speaker: Pablo Jarillo-Herrero (Massachusetts Institute of Technology)
Abstract: The understanding of strongly-correlated quantum matter has challenged physicists for decades. The discovery four years ago of correlated phases and superconductivity in magic angle twisted bilayer graphene has led to the emergence of a new materials platform to investigate strongly correlated physics, namely moiré quantum matter. These systems exhibit a plethora of quantum phases, such as correlated insulators, superconductivity, magnetism, Chern insulators, and more. In this talk I will review some of the recent advances in the field, focusing on the newest generation of moiré quantum systems, where correlated physics, superconductivity, and other fascinating phases can be studied with unprecedented tunability. I will end the talk with an outlook of some exciting directions in this emerging field.
Controlling and Exploring Quantum Matter at the Single Atom Level
Speaker: Immanuel Bloch (Ludwig-Maximilians-Universität, München)
Abstract: More than 30 years ago, Richard Feynman outlined the visionary concept of a quantum simulator forcarrying out complex physics calculations. Today, his dream has become a reality in laboratories around the world. In my talk I will focus on the remarkable opportunities offered by ultracold quantum gases trapped in optical lattices to address fundamental physics questions ranging from condensed matter physics over statistical physics to high energy physcis with table-top experiment.
For example, I will show how it has now become possible to image and control quantum matter with single atom sensitivity and single site resolution, thereby allowing one to directly image individual quantum fluctuations of a many-body system. Such ultrahigh resolution and sensitivity have also enabled us to detect ‘Higgs’ type excitations occurring at 24 orders of magnitude lower energy scales than in high energy physics experiments. I will also show, how recent experiments with cold gases in optical lattices have enabled to realise and probe artificial magnetic fields that lie at the heart of topological energy bands in a solid. Using a novel ‘Aharonov-Bohm’ type interferometer that acts within the momentum space, we are now able to fully determine experimentally the geometric structure of an energy band.
Geometric phases and the separation of the world
Speaker: Michael Berry (H H Wills Physics Laboratory, University of Bristol, UK)
Abstract: The waves that describesystems in quantum physics can carry information about how their environment has been altered, for example by forces acting on them. This effect is the geometric phase. It also occurs in the optics of polarised light, where it goes back to the 1830s. The underlying mathematics is geometric: the phenomenon of parallel transport, which also explains how falling cats land on their feet, and why parking a car in a narrow space is difficult. Incorporating the back-reaction of the geometric phase on the dynamics of the changing environment exposes the unsolved problem of how strictly a system can be separated from a slowly-varying environment, and involves different mathematics: divergent infinite series.
The art of taming light: What we can learn from a bacterium… and beyond
Speaker: Lene Vestergaard Hau (Harvard)
Abstract: We love to manipulate light and have realized that we have a kindred soul in the form of a small bacterium – the cyanobacterium – whose light manipulations result in photosynthesis. This bacterium is in some ways amazing at manipulating light and in some ways…well not so much. But the system is modular and remarkably, the workings of the ‘best’ part of the system were discovered only in recent years but are still not not fully understood. Involved is an enzyme with the capability to perform light driven electrolysis and production of the oxygen in the atmosphere. Our interest in this system has led us to develop a new platform for studies of biomolecules at the single molecule level. I will discuss this platform and its potential for studies of photosynthetic enzymes and of proteins more generally.
Topological Quantum Matter and Entanglement
Speaker: Duncan Haldane (Princeton)
Abstract: Long-range “entanglement” was initially pointed out by Einstein as a strange property predicted by quantum mechanics that he felt was so contrary to common-sense that experiments to test it would surely undermine the quantum theory. But when experimental tests eventually became possible, quantum mechanics was vindicated. In recent years, it has been realized that, instead of merely being an abstract and obscure philosophical issue in the interpretation of the quantum theory, entanglement is in fact perhaps its central feature, and in particular, plays an important role in the new “topological (quantum) states of matter” which have unexpected properties that have given rise to much recent excitement in condensed matter physics. I will describe some examples of this and how ideas from quantum information theory and condensed matter physics have fruitfully joined together.
Defects with Character: Zero-Energy Majorana Modes in Condensed-Matter Systems
Spekaer: Bert Halperin (Harvard)
Abstract: Theory predicts the existence of some peculiar phases of quantum condensed matter systems, in which there are extra degrees of freedom with very low energy, if localized “defects” are present. In one class of these phases, the size of the low-energy Hilbert space corresponds to one-half degree of freedom per defect, and the defects are said too be sites of localized zero-energy “Majorana modes”. The defects are predicted to obey “non-Abelian statistics” — i.e., if various defects can be moved around each other, or if two identical defects can be interchanged, the result will be a unitary transformation on the quantum mechanical state that depends on the order in which operations are performed, but is insensitive to many other details. The talk will introduce these concepts and discuss some attempts to realize them in condensed matter systems.
Physics in 100 years
Speaker: Frank Wilczek (Massachusetts Institute of Technology)
Abstract: Frank Wilczek will discuss the shape of physics, and technology closely related to physics, over the next one hundred years. Themes include the many faces of unification, the re-imagining of quantum theory, and new forms of engineering on small, intermediate, and large scales.